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Top accolade for Rhodes scientist

  • Authors: Mkentane, Luyolo , Holmes, Mike
  • Language: English
  • Type: Article
  • Identifier: vital:7214 , http://hdl.handle.net/10962/d1006425
  • Description: A RHODES University research professor who is championing ground-breaking research into a new cancer diagnosIs and treatment methodology has received a prestigious award after being nominated one of 10 Women of Excellence in South Africa.
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Top jazz group visiting city

Top UN award for leading scientist

  • Authors: National Research Foundation (NRF)
  • Language: English
  • Type: Article
  • Identifier: vital:7193 , http://hdl.handle.net/10962/d1006357
  • Description: Professor Tebello Nyokong holds the DST/NRF funded chair in Medicinal Chemistry and Nanotechnology at Rhodes University
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Towards mineral beneficiation: from basic chemistry to applications

  • Authors: Tshentu, Zenixole
  • Subjects: Metallurgy , Ore-dressing , f-sa
  • Language: English
  • Type: text , Lectures
  • Identifier: http://hdl.handle.net/10948/55783 , vital:53876
  • Description: The role of mineral beneficiation in the survival, growth, development and sustainability of a developing economy cannot be overstated. Our development as a human species has always been involvedly linked with the use of mineral resources from the stone, bronze and iron ages through the early modern eras to the present. In the current modern era, characterized by highly technological equipment, fourth industrial revolution (4IR) and new energy technologies, the role of mineral beneficiation has been elevated. Precious metals find use in the fine chemicals and petrochemicals industry, fuel cells, electrical and electronic products, medical and dentistry applications, jewellery, autocatalysts, and glass and ceramics. The markets for precious metals keep growing and the supply does not meet demand. The development of methods for recovery of metal value from feeds of mineral ore solutions, solutions of spent secondary resources and from mining wastewaters remains of great importance. Further beneficiation strategies for utilization of mineral products in other “value-added” applications are also important for the growth of the mineral markets. The usage of platinum, palladium and rhodium in the autocatalyst industry has grown significantly and this has further elevated the importance of platinum group metals (PGMs), but other areas of application of the strategic metals need to be harnessed. The four stages of beneficiation, namely, primary, secondary, tertiary and final stage, provide an opportunity to beneficiate to greater value for domestic or export use. Our own research work is engaged in several of these stages, from hydrometallurgical recovery of base metals and platinum group metals from feeds of primary mining and solutions of waste secondary resources such as spent catalytic converters and e-waste to the use of metals in “value added” products such as metalbased catalysts for the fuel industry and in metallodrugs. Examples of “value added” products include rhodium as a promoter in molybdenum sulfide as a catalyst for hydrodesulfurization of fuel oil, vanadium as a catalyst in oxidative desulfurization of fuel oil, vanadium and palladium as therapeutic agents for diabetes and cancer, respectively. Current and future work involves (i) the development of metal-selective scavengers to recover lost metal value in mining wastewaters, and (ii) the design of metal-based catalytic materials for refinement of bio-based oils to biofuel as well as for production of green LPG through hydroprocessing. Our work centres around both basic and applied chemistry towards mineral beneficiation and with a bias towards greener production.
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Tribological characteristics of polymers under high force small oscillating angular contact

  • Authors: Bradfield, Jarad Wade
  • Subjects: Tribology , Polymers.
  • Language: English
  • Type: Thesis , Masters , MTech (Mechanical Engineering)
  • Identifier: vital:9637 , http://hdl.handle.net/10948/d1020598
  • Description: This study was intended to establish which polymer material is best suited as the material for bushes used in high force small oscillating angular contact applications as typically found in a large sugar mill coupling. A Tribometer as well as a designed and manufactured Bearing Testing Machine, which simulates and accelerates the wear caused in the intended application, was used to determine the wear rates and coefficients of friction for seven polymer materials. Materials were selected for their superior mechanical and thermal properties. The Tribometer was fitted with a linear reciprocating rig, so as to simulate the small oscillating movement prevalent in the intended application. Each Tribometer test ran for a duration of two hours with a frequency of 33.1 Herts and a normal loading of 40N. Bearing Testing Machine tests were done under similar constraints but with 30kN loading present on the surface of a bushes inner race. These tests had a longer duration of 24 or 48 hours or until intense wearing occurred. Initially both testing methods will be analysed independently of each other in order to try and identify a relationship between the wear rate and coefficient of friction for the different polymers. The different testing methods’ results will be compared to each other in order to establish if a correlation between the materials tested could be found.
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Tribute to jazz pianist Chris McGregor

  • Authors: Seale, Tyrone
  • Language: English
  • Type: Article
  • Identifier: vital:13648 , http://hdl.handle.net/10962/d1012557
  • Description: Photocopied tribute to jazz pianist Chris McGregor from the newspaper Argus. A photo untitled "Chris McGregor, who died in self-exile in France last year" is also with the article.
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Tsimbarume, the Hardened Bachelor

  • Authors: Tracey, Hugh
  • Subjects: African story , Bachelor , Hunter , Expectation
  • Language: English
  • Type: Sound , Story
  • Identifier: vital:15462 , MOA33-04 , http://hdl.handle.net/10962/d1017816 , MOA33
  • Description: Traditional african story of the bachelor who became a hunter and found more than he had expected. , This recording is held at the International Library of African Music. For further information contact ilamlibrary@ru.ac.za , This recording was digitised by the International Library of African Music , Original format: 15ips reel , Equipment used in digitisation: Studer B 67 Tape Recorder; Nagra III , Software: Sound Forge V.6 , Sample rate: 44100Hz 16Bit Stereo
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Tuning the physico-electrochemical properties of novel cobalt (II) octa[(3,5-biscarboxylate)-phenoxy] phthalocyanine complex using phenylamine-functionalised SWCNTs

  • Authors: Agboola, Bolade Oyeyinka , Ozoemena, Kenneth I. , Nyokong, Tebello , Fukuda, Takamitsu , Kobayashi, Nagao
  • Language: English
  • Type: Article
  • Identifier: vital:7238 , http://hdl.handle.net/10962/d1019689
  • Description: The integration of phenylamine-functionalised SWCNTs (SWCNT-phenylamine) with a novel cobalt (II) octa[(3,5-biscarboxylate)-phenoxy] phthalocyanine (CoOBPPc) complex has been described. The physical and electrochemical properties of the CoOBPPc-SWCNT-phenylamine hybrid were evaluated using spectroscopy (IR and UV–vis), field emission scanning electron microscopy and electrochemistry (cyclic voltammetry and electrochemical impedance spectroscopy). Integration of SWCNT-phenylamine resulted in the physical transformation of the CoOBCPPc from the usually bluish colour of cobalt phthalocyanine complexes to a beautiful bright green colour. In addition, the heterogeneous electron transfer kinetics and electrocatalytic properties of the CoOBCPPc were greatly enhanced following the attachment of the SWCNT-phenylamine. The potential electrocatalytic application of the hybrid was tested using β-nicotinamide adenine dinucleotide (NADH) as a model biological analyte. Interestingly, the onset oxidation potential of this analyte was significantly reduced (300 mV) by this hybrid compared to the bare electrode. , Original publication is available at http://dx.doi.org/doi:10.1016/j.carbon.2009.10.023
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Two decades of curriculum transformation: what have we learnt and where do we go from here?

  • Authors: Blignaut, Sylvan
  • Subjects: Curriculum change -- South Africa , Education -- South Africa , f-sa
  • Language: English
  • Type: text , Lectures
  • Identifier: http://hdl.handle.net/10948/16076 , vital:28318
  • Description: In this lecture, I will revisit the implementation of a new curriculum in South Africa’s schooling system and provide a brief overview of why curriculum change is so complex and fraught with difficulties. I will argue that an important reason for the failure of curriculum implementation could be ascribed to a relative neglect by policymakers of “teacher landscapes” or the beliefs teachers have about teaching. I will argue that it “matters what teachers think and do” and if policymakers do not take account of this reality, successful curriculum implementation will remain a challenge.
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Ultra-high precision manufacturing

  • Authors: Abou-El-Hossein, Khaled
  • Subjects: Machining , Diamond turning , f-sa
  • Language: English
  • Type: text , Lectures
  • Identifier: http://hdl.handle.net/10948/20878 , vital:29410
  • Description: One of the engineering areas focusing on the research and development of highvalue components and manufacturing technologies is precision engineering. Precision engineering represents a variety of engineering and science disciplines ranging from areas such as mechanical, electronics and industrial engineering to chemistry, physics, optics and materials science. This paper aims at familiarising the reader with the recent advances in ultra-high precision manufacturing technologies and their applications for the production of various critical components employed in different sectors of the industry. In this paper, the principles of ultra-high precision manufacturing will be discussed followed by examples of its use in various industrial applications. The status of ultra-high precision manufacturing in terms of current research issues and future trends will be discussed. In addition, research activities and projects in the area of precision manufacturing that are currently conducted at the NMMU will be also highlighted. Finally, the author looks forward to presenting herewith comprehensive information that could be useful to the reader and easy to understand by the bigger NMMU’s community.
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Ultrafast Photodynamics of the Indoline Dye D149 Adsorbed to Porous ZnO in Dye-Sensitized Solar Cells

  • Authors: Rohwer, Egmont , Richter, Christoph , Heming, Nadine , Strauch, Kerstin , Litwinski, Christian , Nyokong, Tebello , Schlettwein, Derck , Schwoerer, Heinrich
  • Language: English
  • Type: Article
  • Identifier: vital:7326 , http://hdl.handle.net/10962/d1020576
  • Description: We investigate the ultrafast dynamics of the photoinduced electron transfer between surface-adsorbed indoline D149 dye and porous ZnO as used in the working electrodes of dye-sensitized solar cells. Transient absorption spectroscopy was conducted on the dye in solution, on solid state samples and for the latter in contact to a I−/I3− redox electrolyte typical for dye-sensitized solar cells to elucidate the effect of each component in the observed dynamics. D149 in a solution of 1:1 acetonitrile and tert-butyl alcohol shows excited-state lifetimes of 300±50 ps. This signature is severely quenched when D149 is adsorbed to ZnO, with the fastest component of the decay trace measured at 150±20 fs due to the charge-transfer mechanism. Absorption bands of the oxidized dye molecule were investigated to determine regeneration times which are in excess of 1 ns. The addition of the redox electrolyte to the system results in faster regeneration times, of the order of 1 ns. , Original publication is available at http://dx.doi.org/10.1002/cphc.201200715
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Unemployment Insurance Fund

  • Authors: UIF
  • Subjects: UIF
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/160982 , vital:40574
  • Description: U.I.F. (Unemployment Insurance Fund) is an insurance scheme. The scheme pays money to a worker who has contributed to the fund and who is temporarily unemployed. Money paid into the Fund is paid out to workers who have become unemployed and under certain other circumstances that we will set out below.
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Unsymmetrically Substituted Nickel Triazatetra-Benzcorrole and Phthalocynanine Complexes: Conjugation to Quantum Dots and Applications as Fluorescent “Turn ON” Sensors

  • Authors: Adegoke, Oluwasesan , Nyokong, Tebello
  • Language: English
  • Type: Article
  • Identifier: vital:7311 , http://hdl.handle.net/10962/d1020403
  • Description: We report on the design and application of fluorescent nanoprobes based on the covalent linking of L-glutathione-capped CdSe@ZnS quantum dots (QDs) to newly synthesized unsymmetrically substituted nickel mercaptosuccinic acid triazatetra-benzcorrole (3) and phthalocyanine (4) complexes. Fluorescence quenching of the QDs occurred on conjugation to complexes 3 or 4. The nanoprobes were selectively screened in the presence of different cations and Hg2+ showed excellent affinity in “turning ON” the fluorescence of the nanoprobes. Experimental results showed that the sensitivity of QDs-4 towards Hg2+ was much higher than that of QDs-3 nanoprobe. The mechanism of reaction has been elucidated based on the ability of Hg2+ to coordinate with the sulphur atom of the Ni complex ring and apparently “turn ON” the fluorescence of the linked QDs. , Original publication is available at http://dx.doi.org/10.1007/s10895-013-1317-4
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Utilising new technology to enable sustainable chemical and drug manufacturing in Africa

  • Authors: Watts, Paul
  • Subjects: Drug development , Pharmacology , f-sa
  • Language: English
  • Type: text , Lectures
  • Identifier: http://hdl.handle.net/10948/21000 , vital:29426
  • Description: Over the last few decades organic chemists have developed highly sophisticated chemical reactions to prepare very complex molecules. The pharmaceutical industry uses the methodology that academics develop within research programmes to manufacture drugs to treat a plethora of medical conditions. When unwell, all citizens expect treatment, however it needs to be remembered that the pharmaceutical industry is a business in order to make a profit for its shareholders, and consequently only rich nations can afford access to the most modern treatments available.
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VAT is a public issue - Take a public stand

  • Authors: Co-ordinating Committee on VAT
  • Subjects: VAT
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/168944 , vital:41663
  • Description: Although VAT is now part of daily life, it can be changed. Tax laws are changed all the time in the normal course of events. Public opinion and public action can change VAT. But the public must act. The government’s record of disastrous financial management is costing us all — remember Mossgas? remember Inkathagate? It cannot go on. It is our democratic right and duty to press for changes that will make VAT serve the country. VAT enters every home in the country — it should be debated and managed as a public issue. We have already seen the value of action. There is overwhelming support for our demands to change VAT. That's why the government was forced to amend the VAT system twice in the few weeks before implementation.
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Very Urgent

Vice-Chancellor's address to new students 1976

Vice-Chancellor's Annual Review 2004

  • Language: English
  • Type: Article
  • Identifier: vital:7169 , http://hdl.handle.net/10962/d1006071
  • Description: The highlight of 2004 was the award of both the Vice-Chancellor's Senior Research Award and the SABC2 Shoprite-Checkers Woman of the Year Award (Science and Technology) to Professor Tebello Nyokong, whose research on the development of photosensitisers for photodynamic cancer therapy has received considerable attention.
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Vice-Chancellor's message to new students, 1977

  • Authors: Henderson, Derek Scott
  • Language: English
  • Type: Text
  • Identifier: vital:7356 , http://hdl.handle.net/10962/d1017085
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Vice-chancellor's speech for plaque ceremony: Chapel of St. May and all the Angels

  • Authors: Henderson, Derek Scott
  • Language: English
  • Type: Text
  • Identifier: vital:7570 , http://hdl.handle.net/10962/d1018447
  • Description: Unveiling of the Plaque on the occasion of the Chaepl of St. Mary and all the Angels being declared a national monument, 9 February 1982.
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